Variometer



Aug, 24 1926.

A. H. GREBE VARIOMETER Fild May 25,, 1922 2 Sheets-Sheet 1 Aug, 24 1926'v 597,934

A. H. GREBE I VARIOMETER Filed May 1922 2 Sheets-Shut 2 avwemtozPatented Aug. 24, 1926.

IUNITED STATES PATENT OFFICE.

ALFRED H. GRERE, OF. RICHMOND HILL, NEW YORK, ASSIGNOR TO A. H. GREBE &('10., Y

1110., OF RICHMOND HILL, NEW YORK, A CORPORATION OF NEW YORK.

VARIOMETER.

Application filed May 25, 1922. Serial No. 563,722.

This invention relates to high frequency electrical apparatus and isdlrected more particularly to variable devices, such as variometers,condensers and the like.

The object of the invention is to provide simple, reliable and effectivemeans for making fine adjustments of the variable element of suchelectrical devices, and, for convenience of illustration, the inventionis here applied to a variometer.

In the accompanying drawings, I have shown a construction suitable forcarrying my invention into effect but do not wish to be understood aslimiting myself. to such showing, as various other uses are contemplated, as well as modifications of the present use, which may involvevariation in structural details and other changes within the terms ofthe claims.

In the drawings Fig. 1 is a view in elevation of a portion of the frontface of a panel, showing the main dial control and vernier attachmentfor adjusting the variable element of a variometer or other electricaldevice;

Fig. 2 is a central vertical section on the line s .9 of Fig. 1;

Fi 3 is a transverse section on the line 8 8 of Fig. 2 and Fig. 4 is adetail perspective view of the vernier attachment.

Referring to the drawings, 1 represents the stator of a variometer,which is secured in fixed relation, in any well known manner, to a panel2, and 3 represents the rotor member of the variometer.

The rotor 3 is mounted fast on a shaft 4, rotatable in a bearing 5, ofthe stator frame,

: which shaft extends forward through an opening in the panel and isprovided with a terminal knob 6 and dial 7, containing the usual degreemarkings from zero to one hundred.

The knob and dial are ordinarily formed in one piece and cast, mouldedor pressed up adequate for all main adjustments of the movable elementof a variometer or other variable electrical device, it is difiicult,ifnot impossible, particularly by unskilled per-.

sons, to manipulate the dial by hand with that delicacy of touchnecessary to obtain fine adjustments and there is accordinglyprovided avernier attachment in the form 7, and is controlled and operated by ahand Wheel 11.

As shown, the pinion is carried by a spindle 12, turning in bearingsformed in the free ends of 5 rings 13, 13, which latter act to maintaint e pinion under .yielding tension, in 'driving contact with the innerface of the main dial.

The hand wheel 11 is mounted fast upon the pinion spindle and projects,in part, through a slot 14, in the panel, the arrangement being suchthat a segmental portion only of the hand wheel is exposed and tofacilitate manipulation, the periphery of the hand wheel is notched orotherwise roughened for ready and certain engagement by the finger inrotating it in either direction.

As here illustrated, the movement of the rotor member of the variometeris limited to 180 degrees by means of a screw stud 15, in the front faceof the panel, projecting into a semi-circular slot 16, formed in theinner face of the dial.

While the relative location of the vernier attachment is optional, it ispreferably centered in the vertical plane of the turning axis of therotor member of the variometer and, thus arranged, the operating handwheel is disposed horizontally, in which position it is convenientlyavailable to the hand of the operator.

As the many advantages of the invention will be apparent from theforegoing description, it will not be necessary to list and elaboratethem.

Having thus described my invention, what I claim is 1. In combination a'variable electrical device including a shaft, a panel, said device beingmounted on said anel with said shaft projecting therethroug a knobsocured to one end portion of said shaft, 5

spindle revolubly mounted 1 the a k of secured to said spindle and saidpanel and disposed substantially at right angles to said shaft, afriction wheel secured to said spindle and projecting through an aerture in said panel into engagement wit said knob, anda hand wheelproJectmg through an aperture in said pane 2. In combination, a panel, avariable electrical device mounted in the rear of the anel, a rotatablecontrol member accessible for manipulation from the front of the panelfor varying the device, and a Vernier adjustment comprising a pinionengaging the control member and a hand wheel for rotating the pinion,the said handwheel being mounted in the rear of the panel with a portionof its peripheral face, presented "through a panel opemng formanipulation from the front of the panel.

3. In combination, a anel, a variable electrical device mounted in therear of the panel, a rotatable control member operion, a hand wheelsecured thereto and mounted in the rear of the panel and projectingthrough panel openings, the pinion engaging the said knob, and the handwheel presenting a. portion of its peripheral face for manipulation fromthe front of the panel.

In testimony whereof I aflix my signature.

ALFRED H. GREBE.

